The files in this folder contain coronal hole area data during 2017/12/06-2018/12/06. 

CH_area_HMI.dat : Data derived from HMI results. 
CH_area_GONGz.dat : Data derived from GONGz results. 
CH_area_GONGb.dat : Data derived from GONGb results. 
ADAPT/CH_area_XX.dat : Data derived from one set of the ADAPT ensemble results. For example, CH_area_00.dat is derived from the first set of ADAPT results. 
These datas are saved using ASCII. These files can be opened directly by Tecplot 2009 or later versions. 

Lines 1-10 are the Tecplot header. The data begin from line 11. 
Column 1: Time (decimal year)
Column 2: Total coronal hole area on the solar surface. 
Column 3:  Coronal hole area of the southern polar (SP) region. 
Column 4:  Coronal hole area of the northern polar (NP) region. 